China Daily:

Recently, the media have been highly focused on the sequencing data in the study on the Huanan Seafood Market by researchers from the China CDC. What is your take on this matter from a professional perspective? Thank you.

Tong Yigang:

Currently, no scientific evidence can clearly determine the true origin of the SARS-CoV-2. All animal swab samples mentioned in this paper have tested negative, indicating that no animals at the Huanan Seafood Market were infected. Some environment swabs returned positive, with most of the detected host information from human and some from animals. This also suggests that the cases at the Huanan Seafood Market likely originated from humans rather than animals at the market. Scientists have been working hard to study the origins of the SARS-CoV-2 and have also discovered some coronaviruses in bats that are closer to the SARS-CoV-2 in other countries. However, the exact characteristics of the SARS-CoV-2, how it infects humans, and where it came from still require further research. The media's attention to this matter reflects the public's concern about public health issues. This prompts us, as scientific and technological workers, to provide scientific interpretations of the data from a scientific perspective so that everyone can better understand the data. Thank you.

South China Morning Post:

You just said that blood samples taken before the outbreak of COVID-19 in China have been tested and analyzed. Can you give us more details on that? Thank you.

Zhou Lei:

Thank you for your question. As a matter of fact, we put forward proposals in this regard as early as during the first phase of the joint studies on SARS-CoV-2 origins in Wuhan. China fulfilled its commitment made at that time, and quickly organized a large amount of manpower and material resources, including financial input, to monitor the stored sera of healthy blood donors, which was a huge workload. Let me give you some details. There were 43,850 blood samples involving 30,000 people that needed to be tested. The test results showed that no SARS-CoV-2 antibodies were detected. All of the samples were taken from local blood donors in Wuhan before December 2019. This result clearly confirmed our common findings in the first phase of the joint studies, that is that no cases were found in Wuhan prior to December 2019. As Mr. Shen said just now, we published and shared these results in a timely manner. Thank you.